Combination electric generator with electric clutch

ABSTRACT

A generator and clutch assembly is disclosed for use in a vehicle and includes a rotatable input, an electric generator in a generator housing, a clutch rotor by driven by the rotatable input, and an electric clutch and brake assembly which may be integrated with the generator housing. A field coil may be mounted to an external surface of the generator housing. The generator and clutch may be offset and connected by means of a transfer system having a transfer housing, wherein a field coil is mounted to an external surface of the transfer housing.

CROSS-REFERENCE

This application is a continuation of U.S. patent application Ser. No.14/867,911, filed on Sep. 28, 2015, which claims the benefit of U.S.Provisional Patent App. No. 62/058,577, filed on Oct. 1, 2014, and U.S.Provisional Patent App. No. 62/056,134, filed on Sep. 26, 2014. All ofthese prior applications are incorporated herein by reference in theirentirety.

BACKGROUND OF THE INVENTION

This invention relates to a combination of an electric generator and anelectric clutch for use in a drive system that may be used in vehiclessuch as lawn and garden tractors, stand-on mowers, walk-behind snowthrowers and mowers, and the like.

SUMMARY OF THE INVENTION

The invention comprises a combination of an electric generator and anelectric clutch. In one embodiment disclosed herein, the electric clutchis integrated with the bottom housing member of the generator housing,such that the generator and clutch are located adjacent to one anotherin a low-profile configuration. A field coil of the electric clutch ismounted on an external surface of the generator housing, reducing theheight of the overall unit. In a further embodiment, the generator andclutch are in a side-by-side relationship and a field coil of theelectric clutch is mounted to an external surface of an extension of thegenerator housing, which also serves as a portion of a housing for abelt drive system to connect the generator and clutch to a common inputfrom the prime mover, thus also providing a low-profile configuration.The combination generator and clutch taught herein may be used inconnection with a vehicle, wherein both the electric clutch and otherapparatuses on the vehicle are powered by the generator.

A better understanding of the invention will be obtained from thefollowing detailed descriptions and accompanying drawings, which setforth illustrative embodiments that are indicative of the various waysin which the principals of the invention may be employed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partially schematic drawing of an exemplary vehicleincorporating a combination electric generator and clutch assembly.

FIG. 2 is a side elevational view of a combination electric generatorand clutch assembly.

FIG. 3 is a cross sectional view of the combination electric generatorand clutch assembly of FIG. 2 along line 3-3 in FIG. 2.

FIG. 4 is a partially schematic drawing of an exemplary vehicleincorporating a second embodiment of a combination electric generatorand clutch assembly.

FIG. 5 is a cross sectional view of the combination electric generatorand clutch assembly of FIG. 4 along the line 5-5 in FIG. 4.

FIG. 6 is a partially schematic drawing of another exemplary vehicleincorporating an alternative embodiment of a combination electricgenerator and clutch assembly in accordance with the teachings herein.

DETAILED DESCRIPTION OF THE DRAWINGS

The description that follows describes, illustrates and exemplifies oneor more embodiments of the invention in accordance with its principles.This description is not provided to limit the invention to theembodiment(s) described herein, but rather to explain and teach theprinciples of the invention in order to enable one of ordinary skill inthe art to understand these principles and, with that understanding, beable to apply them to practice not only the embodiment(s) describedherein, but also any other embodiment that may come to mind inaccordance with these principles. The scope of the invention is intendedto cover all such embodiments that may fall within the scope of theappended claims, either literally or under the doctrine of equivalents.

It should be noted that in the description and drawings, like orsubstantially similar elements may be labeled with the same referencenumerals. However, sometimes these elements may be labeled withdiffering numbers or serial numbers in cases where such labelingfacilitates a more clear description. Additionally, the drawings setforth herein are not necessarily drawn to scale, and in some instancesproportions may have been exaggerated to more clearly depict certainfeatures. As stated above, this specification is intended to be taken asa whole and interpreted in accordance with the principles of theinvention as taught herein and understood by one of ordinary skill inthe art.

FIG. 1 illustrates a riding vehicle 100 including a pair of electricwheel motors 139L, 139R to power a pair of driven wheels 116L, 116R. Aset of caster wheels 112 is disposed at the front of frame 110, whichalso supports a mowing deck 117 having a plurality of mowing blades 119.A prime mover 120, which may be an internal combustion engine, is alsodisposed on frame 110 near the rear thereof. It will be understood thatoperator input controls and an operating seat or platform for theoperator of the vehicles disclosed herein would be provided as well. Inthis embodiment, vehicle 100 includes a belt and pulley system 123 thatconnects the output shaft 120 a of prime mover 120 with mowing blades119 via generator clutch brake assembly 160; the connecting belt andpulley system 123 can be of a standard form and is not critical to thisinvention.

Vehicle 100 also includes a controller 132 supported by frame 110 andoperatively connected to battery 124 and to wheel motors 139L, 139R. Aswill be described below, controller 132 also supplies power to electricclutch-brake assembly 162 via conductor 126.

Generator clutch brake assembly 160 is shown in FIGS. 2 and 3, where itcan be seen to include a generator 161 having upper housing member 167and lower housing member 168 forming a single generator housing. Arotatable member, namely input tube 163, extends through generator 161and is supported in part by upper bearing 164 in upper housing member167 and by intermediate bearing 165 in lower housing member 168. A lowerbearing 166 is located in output hub 153 to support rotation of outputhub 153 and pulley 154 when the clutch is engaged. It is preferred thateach of the bearings 164, 165, 166 be sealed bearings to eliminate theneed for additional seals, thereby further reducing the height of theoverall unit.

Input tube 163 also comprises clutch rotor 163 a formed therewith, andit will be understood that the output shaft 120 a of prime mover 120extends into the input tube 163 and is connected thereto by known means,including fastener 170 so that input tube 163 rotates with the primemover output shaft 120 a. It will be understood that other rotatableinput means can be used to connect with an output shaft of the primemover and transfer the rotational movement as outlined herein, in placeof the disclosed input tubes.

Generator 161 comprises a stator 146 fixed within housing members 167and 168 and incorporating coil windings formed in stator 146 in a knownmanner. Magnets 144 and 145 are fixed on upper rotor 142 and lower rotor143, respectively, to rotate adjacent stator 146 and generate anelectric current in a known manner. The output of generator 161 isprovided to battery 124 by means of conductor 125, as shown in FIGS. 1and 2. At least one anti-rotation device 169 is provided to preventrotation of generator clutch brake assembly 160.

To simplify construction and operation, an electric clutch-brakeassembly 162 is used in combination with generator 161 to selectivelyconnect output hub 153 and pulley 154 to input tube 163. A field coil150 is fixed to an external surface of lower housing member 168 ofgenerator 161 by known methods, such as adhesives. This arrangementhelps to reduce the overall height of the assembly 160, conservingground clearance in utility vehicles such as riding vehicle 100. Fieldcoil 150 is powered by conductor 126 connected to controller 132.Clutch-brake disk 151 is fixed to output hub 153 by means of a pluralityof leaf springs 152 and engages the inner surface of brake shroud 155,as shown in FIG. 3, to provide a braking force to output hub 153.Clutch-brake disk 151 is biased to this braking position by means of theplurality of leaf springs 152. When field coil 150 is energized,clutch-brake disk 151 is magnetically pulled to engage clutch rotor 163a, thereby engaging the output hub 153 and pulley 154 with input tube163 to provide rotational output thereto. It will be understood thatfrictional material will be used on the various components as needed.

As shown in FIGS. 2 and 3, brake shroud 155 is secured to the lowerhousing member 168 by a plurality of adjustment mechanisms 172. Gapadjustment mechanisms 172 permit the distance between clutch-brake disk151 and clutch rotor 163 a to be set and adjusted as needed. Each gapadjustment mechanism 172 comprises a wave spring 173 secured between apair of washers 174, and between the locknut 176 and the head of screw175. Thus, the gap adjustment mechanisms 172 act both to retain thebrake shroud 155 and permit necessary adjustments, e.g., as clutch-brakedisk 151 wears.

A second embodiment of a combination electric clutch-brake and generatoris shown in FIGS. 4 and 5, where generator 261 and clutch-brake assembly262 are in a side-by-side relationship. FIG. 4 illustrates a ridingvehicle 200 including a pair of electric wheel motors 239L, 239R topower a pair of driven wheels 216L, 216R. A set of caster wheels 212 isdisposed at the front of frame 210, which also supports a mowing deck217 having a plurality of mowing blades 219. Prime mover 220, which maybe an internal combustion engine, is also disposed on frame 210 near therear thereof. In this second embodiment, vehicle 200 includes a standardbelt and pulley system 223 that connects the output shaft 220 a of primemover 220 with mowing blades 219 via clutch-brake assembly 262.Controller 232 is operatively connected to battery 224 and to wheelmotors 239L, 239R, and also supplies power to electric clutch-brakeassembly 262 via conductor 226. Generator 261 is connected to battery224 by means of conductor 225.

Generator 261 is disposed in a housing comprising upper generatorhousing member 267 and lower generator housing member 268. As will bedescribed in more detail below, upper generator housing member 267includes a flange or extension 267 a. The shape of upper generatorhousing member 267 and its ability to serve multiple functions in thisdesign help to minimize parts and reduce size of the overall unit. Astator 246 is fixed between upper generator housing member 267 and lowergenerator housing member 268 and incorporates coil windings formed instator 246 in a known manner. Magnets 244 and 245 are fixed on upperrotor 242 and lower rotor 243, respectively, to rotate adjacent stator246 and generate an electric current in a known manner.

Generator drive belt 280, and the two pulleys 281, 282 are housedbetween a drive belt cover 279 and the upper generator housing member267 which cooperate to form a transfer housing. Clutch-brake assembly262 is directly connected to output shaft 220 a via a rotatable inputmember, namely input tube 263, which also drives a driving pulley 281. Agenerator drive belt 280 connects the driving pulley 281 to a drivenpulley 282 which then rotates a second rotatable member, namelygenerator drive shaft 283. It will be understood that although a timingbelt system is shown, a standard belt and pulley system disposed in asimilar transfer housing disposed above generator 261 and clutch-brakeassembly 262 could be used in place of drive belt 280 and pulleys 281,282.

Drive belt cover 279 also may include a plurality of mounting bosses 279a spaced appropriately to permit drive belt cover 279 and the entiregenerator clutch-brake assembly 260 to be mounted to the bottom of primemover 220 or to the vehicle frame 210. Drive shaft 283 may be supportedby upper bearing 284 located in drive belt cover 279 and lower bearing285 in lower generator housing member 268.

Electric clutch-brake assembly 262 is used to selectively connect outputhub 253 and pulley 254 to input tube 263. Input tube 263 also comprisesclutch rotor 263 a formed therewith. Output shaft 220 a of prime mover220 will also extend into the input tube 263 and is connected thereto byknown means (not shown) to rotate therewith. Bearings, including upperbearing 264 in drive belt cover 279 and intermediate bearing 265 inupper generator housing member 267, are used to support input tube 263.A lower bearing 266 is located in output hub 253 to support rotation ofoutput hub 253 and pulley 254 when the clutch is engaged.

As in the prior embodiment, a field coil 250 is used to activate theclutch function of the clutch-brake assembly 262, as seen in FIG. 5.Field coil 250 is fixed to an external surface 267 b of the flange orextension 267 a of upper generator housing member 267 to provide acompact arrangement. This arrangement reduces the overall height of theassembly 260, thereby conserving ground clearance in utility vehiclessuch as riding vehicle 200. Field coil 250 is powered by conductor 226connected to controller 232. Braking force is applied to output hub 253by means of clutch-brake disk 251, which is fixed to output hub 253 vialeaf springs 252 and engages the inner surface of brake shroud 255 toprovide the braking force. Leaf springs 252 bias the clutch-brake disk251 to this braking position.

When field coil 250 is energized, clutch-brake disk 251 is magneticallypulled to engage clutch rotor 263 a, thereby engaging the output hub 253and pulley 254 with input tube 263 to provide rotational output thereto.It will be understood that upper generator housing member 267 is shapedappropriately to permit brake shroud 255 to be secured thereto by aplurality of gap adjustment mechanisms 272 similar to that previouslydescribed. Gap adjustment mechanisms 272 are used to control the spacingbetween clutch-brake disk 251 and clutch rotor 263 a as needed.

A further embodiment of a combination electric clutch-brake andgenerator is shown in FIG. 6, which illustrates a riding vehicle 300similar to that shown in FIG. 4 in many respects, and including a pairof electric wheel motors 339L, 339R to power a pair of driven wheels316L, 316R. A set of caster wheels 312 is disposed at the front of frame310, which also supports a mowing deck 317 having a plurality of mowingblades 319. Prime mover 320, which may be an internal combustion engine,is also disposed on frame 310 near the rear thereof. Vehicle 300includes a standard belt and pulley system 323 that connects the outputshaft 320 a of prime mover 320 with mowing blades 319 via a clutch-brakeassembly that is operatively similar to clutch-brake assembly 262. Theprimary difference between generator clutch-brake assembly 360 and thepreviously described generator clutch-brake assembly 260 is that theoutput shaft 320 a is directly connected to and drives the generatorside of generator clutch-brake assembly 360, permitting among otherthings a different orientation of generator clutch-brake assembly 360with respect to vehicle frame 310. Certain modifications to thestructure of the generator clutch-brake assembly would be required topermit this variation, as would be understood by one of skill in theart. Controller 332 is operatively connected to battery 324 and to wheelmotors 339L, 339R, and also supplies power to electric generatorclutch-brake assembly 360 via conductor 326, and the generator componentis connected to battery 324 by means of conductor 325.

While specific embodiments of the invention have been described indetail, it will be appreciated by those skilled in the art that variousmodifications and alternatives to those details could be developed inlight of the overall teachings of the disclosure. Accordingly, theparticular arrangements disclosed are meant to be illustrative only andnot limiting as to the scope of the invention which is to be given thefull breadth of the appended claims and any equivalent thereof.

What is claimed is:
 1. A generator and clutch assembly comprising: agenerator disposed in a generator housing, the generator housingcomprising an upper housing member and a lower housing member, the lowerhousing member having an external surface; a field coil mounted to theexternal surface; a brake shroud mounted to the external surface,wherein the brake shroud is adjustably mounted to the generator housingvia a plurality of adjustment mechanisms, wherein each of the pluralityof adjustment mechanisms separately comprises a wave spring disposedbetween the brake shroud and the external surface, wherein each of theplurality of adjustment mechanisms is separably operable to move thebrake shroud relative to the external surface; a clutch rotor betweenthe field coil and the brake shroud; and a clutch-brake disk between theclutch rotor and the brake shroud to selectively contact the clutchrotor when the field coil is energized and contact the brake shroud whenthe field coil is de-energized.
 2. The generator and clutch assembly ofclaim 1, wherein each of the plurality of adjustment mechanismsseparately further comprises a locknut disposed between the wave springand the external surface, and a screw extending through the brakeshroud, the wave spring and the locknut.
 3. The generator and clutchassembly of claim 1, further comprising a pulley engaged to and drive bythe clutch rotor.
 4. The generator and clutch assembly of claim 1,further comprising an input tube extending through both the upperhousing member and the lower housing member.
 5. A generator and clutchassembly comprising: a generator disposed in a housing; a field coilfixed to an external surface of the housing; a brake shroud adjustablymounted to the housing via an adjustment mechanism, wherein theadjustment mechanism comprises a wave spring disposed between the brakeshroud and the external surface, wherein the adjustment mechanism isoperable to move the brake shroud relative to the external surface; aclutch rotor between the field coil and the brake shroud; and aclutch-brake disk between the clutch rotor and the brake shroud, theclutch-brake disk engaging the brake shroud when the field coil isde-energized and being magnetically attracted to engage the clutch rotorwhen the field coil is energized.
 6. The generator and clutch assemblyof claim 5, wherein the adjustment mechanism further comprises a locknutdisposed between the wave spring and the external surface, and a screwextending through the brake shroud, the wave spring and the locknut. 7.The generator and clutch assembly of claim 5, wherein the housingcomprises an upper housing member and a lower housing member, and theexternal surface to which the field coil is fixed is located on thelower housing member.
 8. The generator and clutch assembly of claim 7,further comprising an input tube extending through both the upperhousing member and the lower housing member.
 9. A drive assembly for usewith a prime mover having an output shaft, the drive assemblycomprising: a housing comprising a plurality of housing members; aclutch-brake assembly supported by the housing and comprising: an inputtube powered by the output shaft, wherein the input tube is directlyengaged with the output shaft of the prime mover, wherein the input tubehas a first axis; a brake shroud engaged to the housing; a field coilmounted to the housing; a clutch rotor connected to the input tubebetween the field coil and the brake shroud; a clutch-brake disk betweenthe clutch rotor and the brake shroud to selectively engage the clutchrotor when the field coil is energized and to engage the brake shroudwhen the field coil is de-energized; and an output hub connected to theclutch-brake disk; and a generator assembly comprising a generatordisposed in the housing and driven by a drive shaft drivingly engagedwith the input tube, the drive shaft having a second axis that isparallel to and offset from the first axis.
 10. The drive assembly ofclaim 9, wherein the plurality of housing members comprises a firsthousing member and a second housing member, and the first housing memberforms an upper housing for the generator assembly, and the secondhousing member forms a lower housing for the generator assembly, and thebrake shroud is engaged to the first housing member.
 11. The driveassembly of claim 10, wherein the first housing member further comprisesa flange, and the brake shroud is engaged to an external surface of theflange.
 12. The drive assembly of claim 11, wherein the brake shroud isadjustably mounted to the external surface of the flange via at leastone adjustment mechanism, the at least one adjustment mechanism operableto move the brake shroud relative to the external surface.
 13. The driveassembly of claim 11, further comprising a cover engaged to the firsthousing member to form a transfer housing, and a transfer mechanismdisposed in the transfer housing to transfer power from the input tubeto the drive shaft of the generator.
 14. The drive assembly of claim 13,wherein the transfer mechanism comprises a drive belt extending betweena first pulley mounted on the input tube and a second pulley mounted onthe drive shaft.
 15. A drive assembly for use with a prime mover havingan output shaft, the drive assembly comprising: a housing comprising aplurality of housing members, wherein the plurality of housing memberscomprises a first housing member and a second housing member, whereinthe first housing member comprises a flange; a clutch-brake assemblysupported by the housing and comprising: an input tube powered by theoutput shaft, the input tube having a first axis; a brake shroud engagedto an external surface of the flange of the first housing member of thehousing, wherein the brake shroud is adjustably mounted to the externalsurface of the flange via a plurality of adjustment mechanisms, whereineach of the plurality of adjustment mechanisms is operable to move thebrake shroud relative to the external surface, and wherein each of theplurality of adjustment mechanisms separately comprises a wave springdisposed between the brake shroud and the external surface; a field coilmounted to the housing; a clutch rotor connected to the input tubebetween the field coil and the brake shroud; a clutch-brake disk betweenthe clutch rotor and the brake shroud to selectively engage the clutchrotor when the field coil is energized and to engage the brake shroudwhen the field coil is de-energized; and an output hub connected to theclutch-brake disk; and a generator assembly comprising a generatordisposed in the housing and driven by a drive shaft drivingly engagedwith the input tube, wherein the first housing member forms an upperhousing for the generator assembly and the second housing member forms alower housing for the generator assembly, wherein the drive shaft has asecond axis that is parallel to and offset from the first axis.
 16. Thedrive assembly of claim 15, wherein the input tube is directly engagedwith the output shaft of the prime mover.